I don't know enough to form judgments, but worth noting these things aren't always predictable at face value. For example, the Swiss People's Party is part of ALDE.
Europe Elects presents it in a way that is a little bit confusing I think. The SVP are a part of the Council of Europe ALDE - but aren't at all affiliated to the EU ALDE (whereas the Green Liberals and the PLR both are). Being a Council of Europe ALDE member doesn't necessarily mean any particular preference for them at the EU level. For instance, the Liechtenstein VU are a member of the Council of Europe ALDE but are affiliated to the EPP. Not at all confusing.
Incidentally, I would bet the bank on the UDC joining ECR if they wanted an EU affiliation. The attachment to ALDE is a historical thing. Broadly because they are/were an agrarian party in the same tradition as the Nordic Centre parties (at least back when the label actually functioned as any sort of an ideological indicator), who
are ALDE members. Hence the reference to "centre" in the French and Italian names of the party.
By the way guys, ECR is like PiS and VOX and Sweden Democrats and Fratelli d'Italia. It's not, you know, a mainstream right group.
